Betweenness Centrality as a Driver of Preferential Attachment in the Evolution of Research Collaboration Networks

TL;DR

This paper demonstrates that betweenness centrality better predicts new authors' attachment in research networks, highlighting the evolving role of global network measures in scientific collaboration growth.

Contribution

It reveals that betweenness centrality, rather than degree, drives preferential attachment in research networks, especially through mediators like supervisors.

Findings

Betweenness centrality outperforms degree in predicting attachment.

Preferential attachment shifts from degree to betweenness over time.

Supervisors act as brokers, influencing network growth.

Abstract

We analyze whether preferential attachment in scientific coauthorship networks is different for authors with different forms of centrality. Using a complete database for the scientific specialty of research about "steel structures," we show that betweenness centrality of an existing node is a significantly better predictor of preferential attachment by new entrants than degree or closeness centrality. During the growth of a network, preferential attachment shifts from (local) degree centrality to betweenness centrality as a global measure. An interpretation is that supervisors of PhD projects and postdocs broker between new entrants and the already existing network, and thus become focal to preferential attachment. Because of this mediation, scholarly networks can be expected to develop differently from networks which are predicated on preferential attachment to nodes with high degree centrality.